package com.lyf.common.utils;

import lombok.extern.slf4j.Slf4j;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

import java.util.Map;

/**
 * @ClassName SpringContextHolder
 * @Description:
 * @Author kang
 * @Date 2020/11/11 21:42
 * @Version 1.0
 */
@Component
@Slf4j
public class SpringContextHolder implements ApplicationContextAware {

    private static ApplicationContext applicationContext;

    /**
     * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.
     */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) {
        SpringContextHolder.applicationContext = applicationContext; // NOSONAR
        String applicationName = applicationContext.getApplicationName();
        log.warn("启动applicationName: {}", applicationName);
    }

    /**
     * 取得存储在静态变量中的ApplicationContext.
     */
    public static ApplicationContext getApplicationContext() {
        checkApplicationContext();
        return applicationContext;
    }

    /**
     * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) {
        checkApplicationContext();
        return (T) applicationContext.getBean(name);
    }

    /**
     * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(Class<T> clazz) {
        checkApplicationContext();
        return (T) applicationContext.getBeansOfType(clazz);
    }

    @SuppressWarnings("unchecked")
    public static <T> T getBeanOfClass(Class<T> clazz) {
        checkApplicationContext();
        return (T) applicationContext.getBean(clazz);
    }


    /**
     * 清除applicationContext静态变量.
     */
    public static void cleanApplicationContext() {
        applicationContext = null;
    }

    private static void checkApplicationContext() {
        if (applicationContext == null) {
            throw new IllegalStateException(
                    "applicaitonContext未注入,请在applicationContext.xml中定义SpringContextHolder");
        }
    }

    /**
     * 获取接口的实现类
     *
     * @param type clazz
     * @return Map<String, T>
     */
    public static <T> Map<String, T> getSpringBeans(Class<T> type) {
        return getApplicationContext().getBeansOfType(type);
    }


}
